Philip Riveley, a substitute teacher at Matawan-Aberdeen Regional High School, has been charged with having sexually explicit conversations with two female students there.Monmouth County Prosecutor's Office

FREEHOLD — A substitute teacher at Matawan-Aberdeen Regional High School has been charged with having sexually explicit conversations with two female students at the school, Monmouth County authorities said today.

Philip Riveley, 29, of Patricia Avenue in the Colonia section of Woodbridge, was arrested Thursday and charged with two counts of child endangerment, said Acting Monmouth County Prosecutor Christopher Gramiccioni.

Gramiccioni said the joint investigation by the prosecutor's office's special victims bureau and the Matawan Police Department revealed Riveley had sexual conversations with a 15-year-old and a 17-year-old high school student.

Riveley is being held in the Monmouth County jail in Freehold on $150,000 full cash bail set by Superior Court Judge John Tassini.

Charlie Webster, spokesman for the prosecutor's office, said the conversations took place in person, although he did not know if there were other ways Riveley and the teens allegedly communicated.

Schools Superintendent David Healy said Riveley was employed by an agency that provides substitute teachers for school districts. Healy said Riveley taught multiple subjects from September through May.

Healy said he does not know the identity of the students and that school officials first learned about the allegations from law enforcement officials.

"The children are the No. 1 priority for us," Healy said. "The children will be appropriately attended to -- whatever that entails -- in terms of support."

He said the school has also pledged to work with the family and cooperate with law enforcement.